Development and Adoption of Integrated Pest Management for Major Pests of Cabbage Using Indian Mustard as a Trap Crop

Use of Indian mustard (Brassica juncea (L.) Czern.) as a trap crop for management of diamondback moth, Plutella xylostella (L.), and leafwebber, Crocidolomia binotalis Zeller, was tried on an experimental farm and farmers’ fields. Preliminary studies indicated that planting of 15 cabbage rows followed by paired mustard rows to manage both pests was useful. The first mustard row is sown 15 days prior to planting, and the other is sown 25 days after. During our studies the intercropped cabbage was successfully raised during the rainy season without insecticidal application, however two sprays with 0.05% cartap hydrochloride were necessary to control diamondback moth during winter. Control of insects colonizing mustard was achieved with 0.1% dichlorvos sprays starting from 15 days after sowing at either 10or 15-day intervals depending on population pressure. Later studies, however, indicated that raising of paired mustard rows at either end of 25 cabbage rows is the most promising planting pattern for successful management of both pests. The intercropped cabbages received two sprays with 0.05% cartap hydrochloride to control diamondback moth and spot application with 0.07% endosulfan and 0.1% phosphamidon to control localized infestation of Helicoverpa armigera (Hübner) and aphids, Brevicoryne brassicae L. respectively. Mustard also attracted other cabbage pests viz., Hellula undalis Zeller and the aphid B. brassicae. Several growers have come forward to adopt this technology as a result of the successful on-farm trials and effective publicity. Introduction Cabbage (Brassica oleracea var. capitata L.) is a commercially important cruciferous vegetable and is cultivated in rainy, winter and summer seasons on 10,753 ha in Karnataka State, India (Anon. 1987). Successful cultivation of this crop is hampered due to the incidence of major defoliating caterpillars like the diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) , and leafwebber , Crocidolomia binotalis Zeller (Lepidoptera: Pyralidae) . Cabbage webworm, Hellula undalis Zeller (Lepidoptera: Pyralidae), tomato fruitworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), and aphids, Brevicoryne brassicae L. (Homoptera: Aphididae) also infect the crop in different areas in various seasons (Nagarkatti and Jayanth 1982; Srinivasan and Veeresh 1986). The cabbage growers resort to weekly insecticide applications, and problems arising from widespread use of insecticides are well known. Inadequate control of major pests on cabbage, especially DBM following application of both organophosphorus insecticides and pyrethroids, has recently been reported (Srinivasan 1988). This pest has developed resistance to a wide variety of insecticides in Asia (Chen and Sun 1986; Sun et al. 1986; Kao et al. 1989). It is therefore necessary to develop a rational pest management program to reduce the number of applications of hazardous chemicals.